Cleaning of hard surfaces, such as floors (vinyl, linoleum, tile, cement), countertops, showers, etc. is well known in the art. Cleaning may be accomplished using cellulosic paper towels and non-woven sheets, as are well known in the art. Nonwoven sheets may be made according to commonly assigned U.S. Pat. Nos. 6,936,330 and/or 6,797,357. Cellulosic paper towels may be made according to commonly assigned U.S. Pat. Nos. 4,191,609 and/or 4,637,859.
Such sheets have been removably attached to manual implements. The implements increase reach, and improve ergonomics. For example, when the hard surface to be cleaned is a floor, the implement allows the user to clean from a standing position, improving comfort over cleaning from a crouched position or on the knees. Manual implements may be made according to commonly assigned U.S. Pat. Nos. 6,305,046 and/or D588,770.
To improve cleaning of soluble stains, wetted and wettable floor sheets have been used. Pre-wetted floor sheets include those having APG polymers, as disclosed in commonly assigned U.S. Pat. No. 6,716,805. Wettable floor sheets have been used with the commercially available Swiffer WetJet (R) appliance. This appliance sprays cleaning solution onto the floor from a replaceable reservoir, as described in commonly assigned U.S. Pat. No. 8,186,898. Cleaning solution chemistry and a reservoir therefor may be made according to commonly assigned U.S. Pat. No. 6,386,392. Floor sheets which absorb cleaning solution from the floor may be made according to commonly assigned U.S. Pat. Nos. 5,960,508, 6,101,661 and/or 7,144,173.
Even with the cleaning solution, tough stain removal may still be limited, for example when cleaning certain types of dried down chunky foods spills. One attempt to further clean tough stains is to include a dedicated scrubbing strip. For example Swiffer Wet Floor sheets have a textured green scrubbing strip disposed on the pad and made according to commonly assigned US 2005/0081888 A1. Such scrubbing strips are discarded with each pad after use. In contrast the WetJet appliance uses a scrubbing strip attach on front edge of the appliance and which is re-used throughout several floor sheets. While these features do improve scrubbing ability, they have the inconvenience of requiring the user to flip the mop head to engage the scrubbing strip with the stain. Furthermore, stains comprising mixed components of sugar, grease and protein, may require excessive scrubbing to completely remove the stain.
Yet another attempt to clean stains from textile fabrics utilizes an absorbent layer placed over the stain. Under heat, pressure, steam the stain may be absorbed into the absorbent layer, as disclosed in commonly assigned U.S. Pat. No. 6,048,368.
But cleaning solution, interposed absorbent layer and scrubbing strips may not effectively clean all stains. For example, kitchen stains may contain sugar, grease and protein. Many cleaning solutions do not effectively handle this type of stain. Accordingly, steam assisted appliances are used to clean such stains.
Floor cleaning steam appliances are well known in the art. Commercially available steam appliances advertise the ability to be able to clean stains without the use of chemicals, by harnessing the energy in the steam. All commercially available steam appliance known to Applicant describe use with a durable, washable floor sheet. The floor sheet is typically a textile micro-fiber or terry cloth.
Commercially available floor cleaning steam appliances include: SHARK, SHARK s3501 STEAM POCKET, SHARK s3251 LITE AND EASY and SHARK s3901 LIFT AWAY PRO, BISSELL STEAM APPLIANCE SELECT, STEAM AND SWEEP HARD FLOOR(adds beater brush), STEAM AND SWEEP PET (adds rubber), BLACK & DECKERSM1620, ORECK STEAM IT, STEAM 100, EUREKA ENVIRO steamer 313A, BIONAIRE 22499, STEAM FAST SF-140, STEAMBOY T1 and SHARPTEK. While these appliances vary in the amount of steam output, mop head shape, and location of the reservoir, all have two common characteristics. The cleaning pad is a washable micro-fiber cloth and use ordinary water dosed from a reservoir (18) to form the steam.
Durable micro-fiber floor sheets, other such cleaning pads offer high surface area, absorbency and mechanical scrubbing capability. These attributes may be helpful when cleaning is achieved with steam and the steam condenses to water. For example, US 2009/0000051 A1, to Rosenzweig, filed Mar. 7, 2008 describes a fabric steam pad with a removable fastener for use with a steam appliance.
But textile microfiber floor sheets encounter problems when used with a steam appliance. For example, such floor sheets require inconvenient washing between uses. Sometimes, the high surface area of the microfiber pad often traps dirt so tightly, that it cannot be easily washed out. Even so, the microfiber pad can lose efficacy after only few cleaning jobs. Thus, the common textile/microfiber/reusable floor sheet commonly used with a steam appliance has several problems.
But such textile floor sheets have even more problems. For example when used with a steam appliance, the floor sheet is dry and requires priming. Priming requires the user to dose steam into the pad for several minutes in order to wet the floor sheet enough to start cleaning process. Priming is inconvenient and requires the user to waste time while waiting sufficient saturation of the floor sheet. Even when primed, the floor sheet may be unevenly wetted, and thus less efficacious than when evenly wetted.
Steam delivered via steam appliance offers the advantage of being able to soften and in some case even dissolve some tough, stuck on soils such as dried chunky food spills. Steam also offers a safe low residue alternative for sanitizing versus other systems that require high levels of chemical actives to sanitize/disinfect.
However, steam has the problem of inefficiently cleaning everyday greasy particulate soils, often found across larger areas of a floor. This problem occurs when steam applied to the pad condenses to water. This water can aide in hydrating the stain to loosen some greasy particulates. However, without detergent, polymer or other wetting agent, the ability of water (even hot water) to suspend particulate, particularly insoluble particulates, is limited. Furthermore, even if the heated condensed water formed by steam can initially wet the floor, the stain quickly cools down and becomes inefficacious.
Since water has high surface tension (73.8 dynes/cm2 at 20 C) compared to many cleaning solutions (35 to 40 dynes/cm 2 at 20 C), water can de-wet the floor leaving wet lines. Upon drying these lines can leave visible streaks. Visual streaks can be a common complaint among users of steam appliances.
Thus, the problem of cleaning floor stains not efficaciously cleaned by dry sheets, wet/wettable floor sheets, and with steam assisted textile sheets persists.